The present invention relates to a home network system capable of collectively receiving various broadcasts, converting received data into common digital data and transmitting the same content broadcast or different content broadcasts to a plurality of display devices.
Recently, there has been available a variety of broadcasting services which are terrestrial analog broadcasting, BS analog broadcasting, CS broadcasting, CATV and so on. Generally, subscribers-viewers selectively receive broadcasts at home terminals according to preferences, local conditions and service contents.
With this, each member in each home may always want to watch preferred programs in a desired way at a particular place.
In addition, the development of the digital technology accelerates the digitalization of the broadcasting services including BS and terrestrial digital broadcasting services.
FIG. 1 is a view for explaining conventional broadcast receiving means for receiving various broadcasting services.
The indoor connection system for receiving, for example, CS (Communication Satellite) broadcasting services in a home is as follows:
The CS broadcast 1 is received by a CS receiving antenna 5 and input to a CS receiver (or a set top box) 9 whereby the received television broadcast signal is converted into a signal to be displayed on a CS display 13.
The connection systems for receiving BS broadcasting and terrestrial broadcasting are analogous to that of the CS broadcasting and comprise respectively antennas 6, 7, receivers 10, 11, and displays 14, 15 in the described order.
Terrestrial broadcasts (VHF, UHF) are received by a so-called television set 17 in which a receiver 11 and a display 15 are combined.
Cable television (CATV) broadcasts transmitted over a cable network are received by a receiver (or a set top box) 12 and converted into a television signal to be displayed on a display unit for CATV 16.
As described above, each viewer (user) has to prepare in his or her home separate receivers and display units for viewing respective broadcasts (CS, BS, Terrestrial and CATV broadcasting services) (except display units usable common to receive the BS broadcasting and the terrestrial broadcasting).
The problems of the prior techniques are as follows:    (1) To enjoy various broadcasting services, the user selects in advance a place (room) for enjoying the broadcasting services, extends thereto respective coaxial cables from respective antenna receivers coupled to respective antennas (aerials), connects the cables to respective specific receivers and finally connects with connecting cables the respective specific receivers to a television receiver(s) (display unit(s)).    (2) In order to enjoy the various kinds of broadcasts in another place (other than the selected place as the above (1)), the user must extend to a newly selected place a coaxial cable from a distributor connected to respective antenna portions.    (3) To change the receiving place (room) for a particular broadcast service to another place (room), the user must extend to a newly selected place (another place) a coaxial cable from a distributor connected to a corresponding antenna portion, disconnect the corresponding receiver, replace it to the new place and then reconnect the receiver to the receiver to the display unit at the new place.    (4) The user cannot receive all kinds of broadcasts on a single television receiver and can enjoy only a limited number of the broadcasting services, each of which is received by a specific receiver connected to a corresponding receiving means of the television receiver.